The present invention relates to a method of preparation of amino-alkyl sulfonic acid compounds and the use of such compounds in the treatment of fluids utilized in the stimulation or other treatment of subterranean formations.
There has been a continuing need for buffering compositions in the pH range of about 6 to 8 for use in the treatment of subterranean formations since not many buffers have been known which are suitable in this pH range. Many fluids utilized in the treatment of subterranean formations, and particularly, those containing viscosifiers must have the pH of the fluid adjusted to a near neutral pH range to activate the viscosifier, any crosslinking agents that may be present or to stabilize the viscosified fluid against premature degradation.
Currently available buffer systems utilize bisulfites to maintain a pH near 7. The bisulfites are undesirable in certain instances because overtreatment can result in interference with the metal crosslinking agents that are utilized in many fluids, and it may react with various breakers utilized to provide a control break of the viscosified fluid. Various phosphates can be used to naturally buffer a fluid in the range of 6 to 8, however, the use of such phosphates is avoided due to interference with crosslinking agents that are utilized in various fluids.
It would be desirable to provide a compound which can be utilized to buffer a fluid for use in the treatment of subterranean formations in the pH range of 6 to 8, which does not adversely affect gel stability, which does not interfere with common fluid breakers and which does not adversely interfere with various crosslinking agents found in such fluids.